For example, a recoil starter is provided to a small engine. The recoil starter includes a spring for rewinding a rope onto a rope reel by the restoring force thereof. For example, in the recoil starter of JP-UM-S59-030217-B, the rope reel (4, corresponding to the reference numeral in JP-UM-S59-030217-B) is rotatably mounted on a rotation shaft (3), and a ratchet (10) is rotatably mounted on the rope reel (4). The ratchet (10) is rotatably mounted on the rope reel (4) at its one end portion, and the other end portion of the ratchet (10) is formed into an engagement pawl. When the rope (7) is pulled to start the engine, the rope reel (4) is rotated, and the ratchet (10) is also rotated. As the ratchet (10) rotates, the engagement pawl is projected outwardly to be engaged with an engagement portion formed in a pulley (1) which is directly coupled to the engine. Thus, the rope reel (4) and the ratchet (10) rotate together with the pulley (1), thereby starting the engine.
In JP-UM-S59-030217-B, a coil spring (5) is disposed onto the rotation shaft (3), and a tip end (5a) of the coil spring (5) is engaged with a guide groove (10a) formed in the ratchet (10). The guide groove (10a) includes a peripherally-extending portion and a radially-extending portion, thereby forming a substantially L-like shape. Since the coil spring (5) is in a compressed state so as not to easily rotate, in the initial stage of the rotation of the rope reel (4), the tip end (5a) of the coil spring (5) moves along the peripherally-extending portion of the guide groove (10a), and does not causes the rotation of the ratchet (10). However, after the tip end (5a) of the coil spring (5) reaches the end of the peripherally-extending portion, it cannot further move in the same direction. Then, the ratchet (10) is caused to outwardly swing from the rope reel (4) such that the engagement pawl thereof projects outwardly to engage with the engagement portion of the pulley (1). Thus, the pulley (1) is also caused to rotate, thereby starting the engine. By releasing the rope (7), the rope reel (4) is reversely rotated by a return spring (6), and is caused to rotate reversely relative to the pulley (1). Thus, the ratchet (4) is also caused to swing reversely back to its initial position while the tip end (5a) of the coil spring (5) moves along the peripherally-extending portion of the guide groove (10a).
For example, the above-mentioned recoil starter may be provided to a snowmobile etc. The snowmobile etc. performs a backward movement by reversing the rotation of its engine. Usually, even if such reverse rotation of the engine is performed, there may be caused no particular adverse effect to the above-mentioned recoil starter as long as the ratchet (10) is in its initial position and is separated from the pulley (1) which is directly coupled to the engine. However, if the rope (7) is pulled in error during the backward movement, there may be caused a problem.
In JP-UM-S59-030217-B, since the L-shaped guide groove (10a) is short, the ratchet (10) can easily be brought from the initial position into the engagement position in which the engagement pawl engages with the engagement portion of the pulley (1). Therefore, when the rope (7) is pulled during the backward movement in which the engine reversely rotates, the ratchet (10) may engage with the pulley (1). In this case, the rope reel (4) is reversely rotated to thereby pull the rope (6) back into the recoil starter. Thus, the components may be damaged, and the safety problem may occur.